A flow disturbing device for vortex-induced vibration of a split box girder bridge

Abstract

The present invention provides a flow disturbance device for vortex-induced vibration of a split box girder bridge, which includes a split box girder and flow disturbance units. An array composed of a number of flow disturbance units is provided at the grooved part of the split box girder; the flow disturbance unit includes a grid, an exciter and a number of elastic members; two adjacent flow disturbance units are combined into an array through the cooperation of the grids. The flow disturbance unit of the present invention is arranged at the grooved part of the split box girder, which destroys the spanwise vortex structure of the vortex at the grooved part of the split box girder, can effectively eliminate the vortex-induced vibration disease of the long-span split box girder bridge. Moreover, the present invention can not only be preliminarily disturbed by the elastic members in the flow disturbance unit when the wind flows through the split box girder, but also remotely control the exciter to actively adjust the airflow ejected by the exciter, without the need to be equipped with an additional gas compression power device, avoiding the change of the aerodynamic characteristics of the bridge by the power device and the air blowing and suction device, reducing the energy consumption, and at the same time eliminating the durability problem caused by the opening of the box girder.

Description

Technical Field

[0001] The present invention relates to a flow disturbing device for vortex-induced vibration of a split box girder bridge, belonging to the technical field of bridge construction. Background Art

[0002] With the increase of the span, modern bridges become more slender and flexible, resulting in wind-induced vibration becoming the main factor affecting the stability during the construction and operation of bridges. In order to cope with the aerodynamic instability problem of long-span bridges, bridge workers creatively adopt split box girders as the main girders of long-span bridges. The split box girder has good flutter performance and is very competitive in the selection of the main girders of long-span bridges. However, the gap between the beam bodies caused by the slotting creates additional space for the shedding and development of vortices, resulting in a more prominent vortex-induced vibration problem of the split box girder at low wind speeds.

[0003] The so-called vortex-induced vibration is a regular self-limiting vibration phenomenon that occurs in bridges at low wind speeds, with characteristics such as a low lock-in wind speed and a high triggering frequency. Although the danger of bridge vortex vibration is not as high as that of divergent aerodynamic instability phenomena such as flutter and galloping, the amplitude caused by it is still sufficient to affect the comfort and safety of vehicle driving on the bridge. Long-term vortex vibration may also cause fatigue damage to the bridge.

[0004] For the vortex-induced vibration phenomenon of split box girders, the current measures taken include aerodynamic measures and active control measures.

[0005] Aerodynamic measures change the flow field around the bridge surface by improving the aerodynamic shape of the bridge, generally being able to achieve the effect of reducing the wind-induced vibration response of the bridge, having advantages such as low cost and easy implementation, and are usually the preferred scheme for bridge vortex vibration control. The commonly used aerodynamic measures mainly include wind nozzles, flow deflectors, flow suppressors, central stabilizer plates, central slotting, etc. However, as a passive control measure, the control effect of aerodynamic measures often only targets specific wind vibration phenomena, such as a certain order of vortex vibration, and its control effect will be greatly reduced when facing multiple complex wind vibration composite responses of the bridge caused by the complex fluid-structure coupling system composed of wind and the bridge.

[0006] Active control measures provide a closed system with the characteristics of information feedback, and can take corresponding feedback measures in real time according to the wind vibration response of the bridge structure to improve the control effect, playing an important role in the wind vibration control of bridge structures.

[0007] If the authorization announcement number is CN115748425A and the patent application name is a steady-state air-blowing device for suppressing the vortex-induced vibration of a split steel box girder and its usage method, a vortex-induced vibration control system including a spoiler deflector and a rotatable air duct is provided. By predicting the possible positions where vortices may shed, the air duct is rotated to jet in multiple directions to suppress the vortex-induced vibration of the bridge. This type of method changes the initial bridge-flow field coupled resonance system, and the control idea is more proactive and active. However, it requires additional configuration of gas storage and gas compression power equipment, and the energy consumption cannot be underestimated; the external air-blowing device will affect the bridge cross-section form and change the aerodynamic characteristics of the bridge; the internal air-blowing device needs to open holes in the steel box girder, increasing the hidden danger of corrosion of the inner wall of the steel box girder and the difficulty of bridge operation and maintenance. It increases the demand for power equipment and energy consumption.

[0008] If the authorization announcement number is CN115897369A and the patent application name is a spoiler device, system and method for the vortex-induced vibration of a split steel box girder, a double-rotor motor spoiler device installed at the slot of the split box girder is provided. By driving the blades to rotate by the motor to interfere with the vortices at the slot to suppress the vortex vibration of the bridge, but this method involves complex electrical and mechanical structures, increasing the difficulty of later maintenance.

[0009] Therefore, the present invention provides a spoiler device for the vortex-induced vibration of a split box girder bridge with a simple structure, easy to maintain, low energy consumption, not affecting the durability of the bridge, and rapid information feedback and easy operation. Summary of the Invention

[0010] The present invention provides a spoiler device for the vortex-induced vibration of a split box girder bridge, which can effectively solve the above problems.

[0011] The present invention is implemented as follows:

[0012] A spoiler device for the vortex-induced vibration of a split box girder bridge includes a split box girder and a spoiler unit. An array composed of a plurality of spoiler units is provided at the slot of the split box girder.

[0013] The spoiler unit includes a frame, an exciter, and a plurality of elastic members; two adjacent spoiler units are combined into an array through the cooperation of the frames, and the exciter is suspended in the middle of the frame by elastic members fixed at four positions, namely, the upper, lower, left, and right positions on the outer surface of the exciter.

[0014] As a further improvement, the exciter includes a sleeve, a first electromagnetic mechanism, a second electromagnetic mechanism, and an airbag;

[0015] The sleeve is a hollow cylinder with closed ends at both horizontal ends. The airbag is located in the middle of the sleeve, and the first electromagnetic mechanism and the second electromagnetic mechanism are symmetrically arranged horizontally on both sides of the airbag.

[0016] As a further improvement, the airbag includes a bladder; steel end parts embedded at both ends of the bladder; several circular frame skeletons fixed at equal distances on the surface of the bladder; and an air nozzle opened on the bladder facing the open direction of the grid.

[0017] As a further improvement, both the first electromagnetic mechanism and the second electromagnetic mechanism include a solenoid valve, a driving rod, and a housing; the housing wraps the solenoid valve and is installed at the inner end of the sleeve, and a driving rod is fixed between the solenoid valve and the steel end part of the airbag.

[0018] As a further improvement, limit baffles are provided at both ends inside the sleeve, so that an axial chute is formed between the limit baffles and the sleeve, and the solenoid valve is accommodated in this chute.

[0019] As a further improvement, the first electromagnetic mechanism and the second electromagnetic mechanism further include a second elastic member sleeved on the outer surface of the driving rod, with one end of the second elastic member fixed to the steel end part of the airbag and the other end fixed to the limit baffle.

[0020] As a further improvement, rectangular holes for improving the transparency rate are opened on the arc-shaped side surface of the sleeve facing the open part of the grid.

[0021] As a further improvement, the first electromagnetic mechanism and the second electromagnetic mechanism further include a power line, with one end of the power line connected to the solenoid valve, and the other end passing through the end of the sleeve and then running along the center of the elastic member, reaching the inner side wall of the grid and then passing through the elastic member downward until the wire trough box at the lower edge of the spoiler unit array.

[0022] As a further improvement, it further includes a wind speed and direction sensor, a solenoid valve control unit, and a cable. A wind speed and direction sensor for measuring the wind speed flowing through the split box girder is provided on one side of the split box girder, and a solenoid valve control unit is provided on the shore. The wire trough box of the spoiler unit, the wind speed and direction sensor, and the solenoid valve control unit are connected through the cable.

[0023] As a further improvement, the solenoid valve control unit includes a main control chip and a solenoid valve controller of the control circuit.

[0024] The beneficial effects of the present invention are as follows: The spoiler units of the present invention are arranged at the slots of the split box girder, which destroys the spanwise vortex structure of the vortices at the slots of the split box girder, can effectively eliminate the vortex-induced vibration diseases of long-span split box girder bridges, and the present invention can not only be preliminarily disturbed by the elastic members in the spoiler units when the wind flows through the split box girder.

[0025] The present invention can also remotely control the vibrator and actively adjust the airflow ejected by the vibrator, without the need to equip an additional gas compression power device, avoiding the change of the aerodynamic characteristics of the bridge caused by the power device and the air blowing and suction device, reducing the energy consumption, and at the same time eliminating the durability problems caused by the openings of the box girder.

[0026] The present invention remotely controls a first electromagnetic mechanism and a second electromagnetic mechanism to compress an airbag located in the middle of a sleeve, and the ejected gas can disrupt the air flow flowing through the segmented box girder.

[0027] The solenoid valve control unit of the present invention is sensitive in response and has the advantages of multi-stage regulation. It can intelligently adjust the opening and closing state and the pulse width modulation rate of the solenoid valve, and specifically adjust the telescopic state and the actuation frequency of the drive rod, so as to change the frequency and volume of the columnar folding airbag ejecting and inhaling gas, achieving the goal of controlling multi-order vortex-induced vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a schematic diagram after the spoiler units of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention form an array.

[0030] Figure 2 It is a simple schematic diagram of the structure of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention.

[0031] Figure 3 It is a three-dimensional structure schematic diagram of a spoiler unit of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention.

[0032] Figure 4 It is an exploded view of the structure of an exciter of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention.

[0033] Figure 5 It is a semi-sectional three-dimensional structure schematic diagram of an airbag of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention.

[0034] Figure 6 It is a schematic diagram of the structure of the outer surface of a frame of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention.

[0035] Figure 7 It is a schematic diagram of the structure of the exciter in the air-blowing state of a spoiler device for vortex-induced vibration of a segmented box girder bridge provided by an embodiment of the present invention.

[0036] Figure 8This is a schematic diagram of the air intake state structure of the exciter of a flow disturbance device for vortex-induced vibration of a split box girder bridge provided by an embodiment of the present invention.

[0037] In the figure: split box girder 10, flow disturbance unit 20, wind speed and direction sensor 30, solenoid valve control unit 40, cable 50, grid 201, exciter 202, elastic member 203, inverted wedge-shaped cross-section guide rail 211, inverted wedge block 212, sleeve 221, first electromagnetic mechanism 222, second electromagnetic mechanism 223, airbag 224, limit baffle 225, chute 226, bladder body 2241, steel end 2242, pitch circle framework 2243, air nozzle 2244, solenoid valve 2221, drive rod 2222, second elastic member 2223, housing 2224, power cord 2225. Detailed implementation mode

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without any creative effort belong to the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the embodiments of the present invention, and all other embodiments obtained by those of ordinary skill in the art without any creative effort belong to the scope of protection of the present invention.

[0039] In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0040] Refer to Figures 1-8 As shown, the present invention provides a specific implementation mode regarding a flow disturbance device for vortex-induced vibration of a split box girder bridge, including a split box girder 10 and a flow disturbance unit 20. An array composed of a plurality of flow disturbance units 20 is provided at the grooved part of the split box girder 10.

[0041] The flow disturbance unit 20 includes a grid 201, an exciter 202, and a plurality of elastic members 203. Adjacent two flow disturbance units 20 are combined into an array through the cooperation of the grids 201. The exciter 202 is suspended in the middle of the grid 201 through elastic members 203 fixed at four positions on the outer surface of the exciter 202, up, down, left, and right. Refer to Figures 1 to 3 As shown.

[0042] Furthermore, referring to Figure 6 As shown, among the four non-open surfaces of the grid 201, U-shaped connected inverted wedge-section guide rails 211 are provided on two of the surfaces, and inverted wedge blocks 212 are provided on the other two. The inverted wedge blocks 212 are engaged and locked with the U-shaped connected inverted wedge-section guide rails 211 on the non-open surfaces of the grid 201 of the adjacent blowing and disturbing flow units 20, so as to assemble an array suitable for grooving the split box girder 10, facilitating modular assembly and disassembly, being convenient for installation on newly built bridges and existing bridges, not affecting the split box girder and pavement facilities, etc., and achieving the effects of simple structure and easy maintenance.

[0043] In one specific embodiment, the size of the grid 201 is 1.25m×1.25m×1.25m, which is convenient for assembly and transportation.

[0044] In one specific embodiment, the top surface size of the inverted wedge block 26 on the surface of the grid 201 is 1150mm×1150mm, and the bottom size is 1100mm×1100mm; the top width of the inverted wedge guide rail 25 is 75mm, and the bottom width is 50mm.

[0045] The disturbing flow unit 20 of the present invention is arranged at the grooving position of the split box girder 10, which destroys the spanwise vortex structure of the vortex at the grooving position of the split box girder 10, can effectively eliminate the vortex-induced vibration disease of the long-span split box girder bridge. Moreover, the present invention can not only initially disturb the air flow when the air flows through the split box girder 10 through the elastic member 203 in the disturbing flow unit 20, but also remotely control the exciter 202 to actively adjust the air flow ejected by the exciter 202, without the need to be equipped with an additional gas compression power device, avoiding the change of the aerodynamic characteristics of the bridge by the power device and the blowing and suction device, reducing the energy consumption, and at the same time eliminating the durability problems caused by the opening of the box girder.

[0046] Specifically, the exciter 202 includes a sleeve 221, a first electromagnetic mechanism 222, a second electromagnetic mechanism 223, and an airbag 224; the sleeve 221 is a hollow cylinder with closed ends at both horizontal ends, the airbag 224 is located in the middle of the sleeve 221, and the first electromagnetic mechanism 222 and the second electromagnetic mechanism 223 are horizontally symmetrically arranged on both sides of the airbag 224.

[0047] In this embodiment, the first electromagnetic mechanism 222 and the second electromagnetic mechanism 223 are remotely controlled to compress the airbag 224 located in the middle of the sleeve 221, and the ejected gas can disrupt the air flow passing through the segmented box girder 10. The specific operation is as follows: The first electromagnetic mechanism 222 and the second electromagnetic mechanism 223 work simultaneously, or they can operate alternately, or only the first electromagnetic mechanism 222 or the second electromagnetic mechanism 223 operates. For more detailed transmission details, see below. The frequency and volume of the gas ejected and inhaled by the airbag 224 are adjusted specifically to achieve the goal of controlling multi-order vortex-induced vibration.

[0048] Moreover, the first electromagnetic mechanism 222, the second electromagnetic mechanism 223, and the airbag 224 are integrated within a cylindrical sleeve, reducing the projected area. The sleeve 221 is suspended at the center of the steel grid with open upper and lower surfaces, which can minimize the impact of the device on the slotting and ventilation rate of the segmented box girder 10 to the greatest extent and ensure the flutter performance of the box girder.

[0049] Among them, the airbag 224 includes a bladder 2241; steel end parts 2242 embedded at both ends of the bladder 2241; several circular frame members 2243 fixed equidistantly on the surface of the bladder 2241. The circular frame members 2243 are used to support the bladder 2241 to prevent it from tearing, and can also move evenly when the airbag 224 is axially compressed or restored. The air nozzle 2244 opened on the bladder 2241 faces the open direction of the grid 201, and can face the air flow coming through the segmented box girder 10, with good flow disturbance effect and no deviation. Refer to Figure 5 and Figure 7 as shown.

[0050] In one specific embodiment, the diameter of the largest circular frame member 24 of the airbag 224 is 320 mm, the diameter of the smallest circular frame member is 240 mm, the number of folds of the airbag 224 is 6 folds, the maximum length after inhalation is 290 mm, and the minimum length after blowing is 70 mm.

[0051] In one specific embodiment, the number of the air nozzles 2244 is 2 groups, two in each group, and the two groups are respectively arranged at the centers of the two outer surfaces of the bladder 2241 facing the open direction of the grid 201. Compared with having only one air nozzle 2244, the air output and air intake of the two air nozzles 2244 are larger, and the time taken is shorter when the bladder 2241 is axially compressed or restored.

[0052] Among them, both the first electromagnetic mechanism 222 and the second electromagnetic mechanism 223 include an electromagnetic valve 2221, a drive rod 2222, and a housing 2224. The housing 2224 wraps the electromagnetic valve 2221 and is installed at the inner end of the sleeve 221. A drive rod 2222 is fixed between the electromagnetic valve 2221 and the steel end part 2242 of the airbag 224.

[0053] The driving rod 2222 mentioned here refers to the solenoid valve driving rod. The driving rod is made of silicon steel with good demagnetization performance, and the surface is provided with the same number of rectangular chutes as the axial rotation limiting blocks on the inner ring surface of the solenoid valve. When the solenoid valve 2221 is energized, it drives the driving rod 2222 to squeeze the airbag 224, so that the gas ejected from the airbag 224 can disrupt the air flow flowing through the split box girder 10.

[0054] In one specific embodiment, the total length of the driving rod 2222 connected to the airbag 224 is 150 mm, the diameter is 120 mm, and the maximum stroke is 110 mm.

[0055] Further, limiting baffles 225 are provided at both ends inside the sleeve 221, so that an axial chute 226 is formed between the limiting baffles 225 and the sleeve 221, and the solenoid valve 2221 is accommodated in this chute 226.

[0056] Furthermore, a rectangular chute is opened in the exact middle of the limiting baffle 225, and a rectangular block is provided on the outer surface of the housing 2224. The rectangular block of the housing 2224 meshes with the rectangular chute to limit the circumferential rotation direction of the solenoid valve 2221.

[0057] Further, the first electromagnetic mechanism 222 and the second electromagnetic mechanism 223 also include a second elastic member 2223 sleeved on the outer surface of the driving rod 2222. One end of the second elastic member 2223 is fixed to the steel end 2242 of the airbag 224, and the other end is fixed to the limiting baffle 225. When the solenoid valve 2221 is de-energized, the elasticity of the second elastic member 2223 itself will drive the driving rod 2222 to return to its original position to achieve reset, so that the gas in the airbag 224 gradually fills up, as shown in Figure 8 shown.

[0058] In one specific embodiment, the original length of the second elastic member 2223 sleeved on the driving rod is 40 mm, and when the columnar airbag 224 is inflated to the limit state, the stretching length of the second elastic member 2223 is 150 mm.

[0059] Among them, a rectangular hole 227 for improving the light transmittance is opened on the arc-shaped side surface of the sleeve 221 facing the open end of the grid 201.

[0060] In one specific embodiment, the sleeve 221 has a height of 720 mm, a diameter of 360 mm, the axial opening height on the surface of the steel sleeve is 120 mm, and the central angle corresponding to the rectangular hole 227 is 80°.

[0061] Among them, the first electromagnetic mechanism 222 and the second electromagnetic mechanism 223 further include a power cord 2225. One end of the power cord 2225 is connected to the solenoid valve 2221, and the other end passes out from the end of the sleeve 221. After being wrapped with an insulating sleeve, it runs along the center of the elastic member 203, reaches the inner side wall of the frame 201, then passes through the elastic member 203 downward until the wire trough box at the lower edge of the spoiler unit 20 array. After being summarized at multiple levels, it penetrates into the split box girder 10 internally until it is connected to the solenoid valve control unit 40 on the shore.

[0062] The present invention further includes a wind speed and direction sensor 30, a solenoid valve control unit 40, and a cable 50. A wind speed and direction sensor 30 for measuring the wind speed flowing through the split box girder 10 is provided on one side of the split box girder 10, and a solenoid valve control unit 40 is provided on the shore. The wire trough box of the spoiler unit 20, the wind speed and direction sensor 30, and the solenoid valve control unit 40 are connected through the cable 50, as shown in Figure 2 shown.

[0063] Further, the solenoid valve control unit 40 includes a solenoid valve controller with a main control chip and a control circuit.

[0064] Among them, the main control chip receives the input signal of the wind speed and direction sensor 30 and outputs a multi-level level signal to the control circuit;

[0065] Among them, the control circuit can modulate a multi-level carrier signal according to the multi-order vortex-induced vibration locking wind speed of the bridge.

[0066] Further, the solenoid valve control unit 40 is powered by a power supply and is centrally installed in a control cabinet on the shore. Its output end is connected to the solenoid valve 2221, and it is sequentially numbered according to the slotting position of the solenoid valve 2221 in the split box girder 10 and the row and column positions of the spoiler unit 20.

[0067] The working principle of the present invention:

[0068] According to the different-order vortex-induced vibration locking wind speeds of the bridge given by the wind tunnel test, the carrier signal of the solenoid valve control unit 40 is set. The signal of the wind speed and direction sensor 30 is input into the solenoid valve control unit 40 through the cable 50. When the oncoming wind speed enters the bridge vortex-induced vibration locking wind speed range, the level signal value output by the main control chip will be greater than the carrier signal in the control circuit, and the solenoid valve will open; otherwise, the solenoid valve will close. The pulse width modulation rate of the solenoid valve is set so that the solenoid valve cyclically experiences a cycle of opening and closing that is consistent with the period of the bridge vortex-induced vibration, realizing that the solenoid valve control unit 40 is sensitive and has the advantages of multi-level regulation, and can intelligently adjust the opening and closing state and the pulse width modulation rate of the solenoid valve.

[0069] When the wind speed and direction sensor 30 monitors that the oncoming wind speed enters the vortex-induced vibration locking range of the bridge, the reference values of the vortex-induced vibration locking wind speeds and dominant frequencies of different orders of the bridge given by the wind tunnel test are used to determine the dominant frequency of the bridge vortex-induced vibration. , the solenoid valve control unit 40 adjusts the actuation frequency of the telescopic drive rod 2222 of the solenoid valve 2221 to , so the blowing and suction frequency of the airbag 224 is also .

[0070] The blowing and suction frequency of the airbag 224 described here refers to the number of times the airbag 224 completes blowing and suction within a 1-second time interval.

[0071] Set the inflation volume of each airbag 224 to liters, and the diameter is meters. The calculation method of the average telescopic speed of the drive rod 2222 is as follows:

[0072]

[0073] The length of the drive rod 2222 is calculated as follows:

[0074]

[0075] The solenoid valve control unit 40 adjusts the current of the solenoid valve 2221 in the flow direction according to the dominant frequency of the bridge vortex-induced vibration and the set inflation volume. After being energized, the solenoid valve 2221 pops out the drive rod 2222 at a certain speed, driving the airbag 224 to compress towards the center. The gas in the airbag 224 is ejected in the up and down directions through the air nozzle 2244, destroying the flow field at the grooved part of the split box girder 10. The telescopic second elastic member 2223 is stretched due to the drive of the drive rod 2222.

[0076] After completing the blowing, the solenoid valve control unit 40 makes the solenoid valve 2221 in the off state, and the electromagnetic force acting on the drive rod 2222 disappears. The stretched second elastic member 2223 quickly retracts to the natural state, driving the drive rod 2222 to reset. The airbag 224 is expanded under the drive of the drive rod 2222, and the vortex formed by the upstream box girder at the grooved part is sucked into the airbag 224 through the air nozzle 2244, thereby destroying the vortex structure at the grooved part of the split box girder 10.

[0077] The spoiler unit 20 is arranged at the grooved part of the split box girder 10. The vortices generated by the upstream box body enter the grooved area, causing the vibrator 202 located at the center of the grid 201 to be impacted and oscillate reciprocally up and down. The air flow induced by the oscillation disturbs the vortex structure in the wake, causing the wake vortex structure to be disordered and fragmented, thereby reducing the influence of the wake on the pressure distribution on the surface of the box girder, that is, the initial disturbance.

[0078] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A flow disturbing device for vortex-induced vibration of a split box girder bridge, characterized in that It includes a split box girder (10) and a flow disturbing unit (20). An array composed of a number of flow disturbing units (20) is provided at the grooved part of the split box girder (10). The flow disturbing unit (20) includes a frame grid (201), an exciter (202) and a number of elastic members (203). Two adjacent flow disturbing units (20) are combined to form an array through the cooperation of the frame grids (201). The exciter (202) is suspended in the middle of the frame grid (201) through elastic members (203) fixed at four positions of the upper, lower, left and right outer surfaces of the exciter (202). The exciter (202) includes a sleeve (221), a first electromagnetic mechanism (222), a second electromagnetic mechanism (223) and an airbag (224). The sleeve (221) is a hollow cylinder with closed ends at both horizontal ends. The airbag (224) is located in the middle of the sleeve (221). The first electromagnetic mechanism (222) and the second electromagnetic mechanism (223) are horizontally symmetrically arranged on both sides of the airbag (224). Remotely control the first electromagnetic mechanism and the second electromagnetic mechanism to compress the airbag located in the middle of the sleeve, and the ejected gas can disturb the airflow flowing through the split box girder.

2. The flow disturbance device for vortex-induced vibration of a split box girder bridge according to claim 1, characterized in that The airbag (224) includes a bladder (2241). Steel end parts (2242) embedded at both ends of the bladder (2241). A number of circular frame members (2243) fixed at equal distances on the surface of the bladder (2241). The air nozzle (2244) opened on the bladder (2241) faces the open direction of the frame grid (201).

3. The flow disturbing device for vortex-induced vibration of a split box girder bridge according to claim 2, wherein Both the first electromagnetic mechanism (222) and the second electromagnetic mechanism (223) include a solenoid valve (2221), a drive rod (2222) and a housing (2224). The housing (2224) wraps the solenoid valve (2221) and is installed at the inner end of the sleeve (221). A drive rod (2222) is fixed between the solenoid valve (2221) and the steel end part (2242) of the airbag (224).

4. The flow disturbing device for vortex-induced vibration of a split box girder bridge according to claim 3, wherein, Limit baffle plates (225) are arranged at both ends inside the sleeve (221), so that an axial sliding groove (226) is formed between the limit baffle plates (225) and the sleeve (221), and the solenoid valve (2221) is accommodated in this sliding groove (226).

5. The flow disturbance device for vortex-induced vibration of a split box girder bridge according to claim 4, characterized in that, The first electromagnetic mechanism (222) and the second electromagnetic mechanism (223) also include a second elastic member (2223) sleeved on the outer surface of the drive rod (2222). One end of the second elastic member (2223) is fixed to the steel end part (2242) of the airbag (224), and the other end is fixed to the limit baffle plate (225).

6. The flow disturbing device for vortex-induced vibration of a split box girder bridge according to claim 3, wherein, Rectangular holes (227) for improving the transparency are opened on the arc-shaped side surface of the sleeve (221) facing the open part of the frame grid (201).

7. The flow disturbing device for vortex-induced vibration of a split box girder bridge according to claim 5, wherein, The first electromagnetic mechanism (222) and the second electromagnetic mechanism (223) further include a power line (2225). One end of the power line (2225) is connected to the solenoid valve (2221), and the other end passes out of the end of the sleeve (221), then follows the center of the elastic member (203) to reach the inner side wall of the grid (201), and then passes downward through the elastic member (203) until the wire trough box at the lower edge of the spoiler unit (20) array.

8. The flow disturbing device for vortex-induced vibration of a split box girder bridge according to claim 7, wherein It further includes an air velocity and direction sensor (30), a solenoid valve control unit (40), and a cable (50). An air velocity and direction sensor (30) for measuring the air velocity flowing through the split box girder (10) is provided on one side of the split box girder (10), and a solenoid valve control unit (40) is provided on the shore. The wire trough box of the spoiler unit (20), the air velocity and direction sensor (30), and the solenoid valve control unit (40) are connected through the cable (50).

9. The flow disturbing device for vortex-induced vibration of a split box girder bridge according to claim 8, characterized in that, The solenoid valve control unit (40) includes a solenoid valve controller with a main control chip and a control circuit.

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